get key associated with max value in a Dictionnary?

Here is a quick code example that builds on the previous code:

Option Strict Off

Imports System
Imports System.Collections.Generic
Imports NXOpen
Imports NXOpen.UF

Module Module44

Dim theSession As Session = Session.GetSession
Dim ufs As UFSession = UFSession.GetUFSession

Sub Main()

Dim lw As ListingWindow = theSession.ListingWindow

Dim workPart As Part = theSession.Parts.Work

lw.Open()

Dim theNodes As New List(Of ExampleClass)
theNodes.Add(New ExampleClass("5001", 10.1))
theNodes.Add(New ExampleClass("5002", 20.2))
theNodes.Add(New ExampleClass("9999", 99.9))
theNodes.Add(New ExampleClass("6001", 30.3))
theNodes.Add(New ExampleClass("6002", 40.4))

lw.WriteLine("'theNodes' original order:")
For Each temp As ExampleClass In theNodes
lw.WriteLine("ID: " & temp.ID & ", stress value: " & temp.Stress.ToString)
Next
lw.WriteLine("")

Dim someNode As ExampleClass
'look for ID = 9999
'simulate using some existing variable with value of the ID to find
Dim theID As String = "9999"
Dim newStressValue As Double = 1234
If theNodes.Exists(Function(x) x.ID = theID) Then
lw.WriteLine("node with ID = " & theID & " found, updating stress value to '" & newStressValue.ToString & "'")
someNode = theNodes.Find(Function(x) x.ID = theID)
someNode.Stress = newStressValue
Else
lw.WriteLine("node with ID = " & theID & " NOT found")
End If

'report ID and stress values
lw.WriteLine("current values:")
For Each temp As ExampleClass In theNodes
lw.WriteLine("ID: " & temp.ID & ", stress value: " & temp.Stress.ToString)
Next
lw.WriteLine("")

End Sub

Function CompareExampleClassByStress(ByVal x As ExampleClass, ByVal y As ExampleClass) As Integer

If x.Stress > y.Stress Then
Return 1
End If

If x.Stress < y.Stress Then
Return -1
End If

If x.Stress = y.Stress Then
Return 0
End If
End Function

End Module

Public Class ExampleClass

Private _id As String
Public Property ID() As String
Get
Return _id
End Get
Set(ByVal value As String)
_id = value
End Set
End Property

Private _stress As Double
Public Property Stress() As Double
Get
Return _stress
End Get
Set(ByVal value As Double)
_stress = value
End Set
End Property

Public Sub New(ByVal id As String, ByVal stressValue As Double)
_id = id
_stress = stressValue
End Sub

End Class

The only real new stuff concerns the .Find and .Exists methods of the list object.

If theNodes.Exists(Function(x) x.ID = theID) Then

The code above checks for the existence of an element in the list with a certain ID value. If we have a list of simple value types (such as string or integer), then looking for a certain value is easy. However, if we have a list of custom objects, we need to know what property value(s) we are interested in finding. Similar to when we sorted the list, we now need to write a custom function to test the list member to see if its property value(s) match what we are looking for. Since our function is very simple, we can write it entirely within the 'argument input' of the .Exists method. It follows this format: .Exists(FunctionDeclaration FunctionBody). First we declare that we are using a function (as opposed to a subroutine); we don't need to give it a proper name, since we won't be calling it from anywhere else. So, "Function(x)" says that we are using a function and the parameter will be named "x". The function used for the .Exists method must return a True or False value; the equality test, x.ID = theID, does just that. The .Exists method is responsible for passing in each member of the list to our function. If the function returns True for any member of the list, the .Exists function knows there is at least one member that matches, so it returns True and stops looking.

Writing the function inline like this comes in handy when the function is very simple. We could have created a 'proper' function and used it instead; something like:

.
.
If theNodes.Exists(AddressOf FindID) Then
lw.WriteLine("node exists, using FindID function")
Else
lw.WriteLine("node does NOT exist, using FindID function")
End If
.
.
Function FindID(ByVal theItem As ExampleClass) As Boolean

If theItem.ID = "9999" Then
Return True
Else
Return False
End If

End Function

Perhaps this makes it a bit more clear as to what is happening; however, the inline function is a bit more flexible.